1. Field of the Invention
The present invention relates to a hand-held power tool with an integrated chuck for receiving a percussion working tool in particular such as chisel hammer, combi-hammer, etc. with an internal cooling blower for producing a cooling air flow for cooling the power tool motor.
2. Description of the Prior Art
With electrical hand-held power tools which are used for percussion destruction of stone materials, the limitation of penetration of an abrasive dust in dust-sensitive units such as die pre-chamber or inner surface of the guide sleeve of the percussion tool-receiving chuck, represents a substantial contribution to increase of maintenance-free service life.
German Publication DE 19724532 discloses a rotary-percussion hand-held power tool with an integrated chuck for receiving a percussion working tool and in which sealing rings are provided between the work spindle and an actuator sleeve displaceable axially relative to the spindle. The sealing rings dusttightly close, in the chuck at the power tool side thereof, the locking chamber with the locking member or members.
German Publication DE 196 26 254 discloses a rotary-percussion hand-held power tool in which a cooling air for cooling the motor flows through a cooling air channel, which is located in the outer housing radially outwardly of the work spindle, up to a percussion tool-receiving chuck that is integrally formed with the work spindle at the spindle working tool-side. The cooling air is used, in a free space that adjoins the work spindle radially outwardly, for cooling the outer surface of the guide sleeve that is strongly heated as a result of the sliding friction caused by the limited axial displacement therein of the percussion working tool.
German Publication DE 35 240 36 discloses a rotary-percussion hand-held power tool in which a cooling air for cooling the tool motor flows in the work spindle of the power tool along the die up to a combi-tool-receiving chuck, which is releasably mounted on the work spindle at its working tool side, and is used there for blowing out abrasive dust that penetrated into the die pre-chamber from the die pre-chamber. The cooling air, which flows in the power tool between the work spindle and the outer housing, penetrates, through the radial openings in the work spindle, in the axial region of the elongate, prismatic die that forms cooling channels in the work spindle. However, such elongate die is not suitable, because of its high acoustic impedance, for hand-held power tools with a high impact power over 1000 watt.
An object of the invention is to provide a percussion tool-receiving chuck for a high-power percussion hand-held power tool.